Several aspects are to be considered while discussing the use of dental materials including (a) the chemical and biologic properties of the materials and (b) the attitudes and beliefs of dentists and patients [15]. The restoration of posterior teeth using resin composite has been increasingly taught in dental schools worldwide [18–23]. Furthermore, amongst several measures mentioned in the text and annexes of the Minamata Convention on Mercury, it also states important measures such as setting national objectives aiming at minimizing use of dental amalgam, promoting use of cost-effective and clinically effective mercury-free alternatives for dental restoration, restricting the use of dental amalgam to its encapsulated form, promoting the use of best environmental practices in dental facilities to reduce releases of mercury and mercury compounds to water and land, and encouraging representative professional organizations and dental schools to educate and train dental professionals and students on the use of mercury-free dental restoration alternatives and on promoting best management practices [11]. At the backdrop of this information, the aim of the present study was to assess the attitudes of dentists and interns in Riyadh, Saudi Arabia regarding the use of dental amalgam. A comparative assessment of the attitudes of dentists and fresh dental graduates (interns) will give a broader perspective of the differences in attitudes.
The majority of the participants in this study (80.7%) reported that they do not use dental amalgam frequently in their clinical practice which is consistent with the results of previous studies which found that amalgam was used less frequently compared to resin composite [2, 3]. Among those who use dental amalgam frequently, it is noteworthy that a significantly higher number of participants working in public sector compared to those working in private sector used amalgam (P = 0.004). Furthermore, a significantly higher number of participants working in private sector agreed on replacing good amalgam restoration with resin composite compared to those working in public sector (P < 0.001). These results concur with those of previous studies [15, 16] and may be due to the fact that private practitioners are more market-oriented, as elucidated by the authors of these studies. A significantly higher number of fresh dental graduates reported that they were not using dental amalgam frequently compared to experienced dentists (P < 0.001). This may indicate a positive influence of the attributes of the Minamata Convention on Mercury [11] on the dental curriculum regarding the use of dental amalgam.
The majority of the participants in this study (61.6%), a significantly higher number of male participants and those working in public sector reported that amalgam is not an occupational risk factor at their workplace which is contrary to the results of a study among Nordic dentists [15]. Only a small proportion of Nordic dentists were worried about amalgam as an occupational risk factor. Furthermore, sex or working sector of the Nordic dentists did not affect this view.
Dentists may utilize a variety of sources to support decisions in clinical practice which may vary depending on the years since graduation and between general practitioners and specialists [24]. A significantly higher number of dentists used amalgam frequently compared to fresh dental graduates in the present study (P < 0.001). Restorative decision-making is complex and is influenced by several factors. Dentists reportedly are more likely to prefer amalgam for patients who exhibit high caries experience [12, 14] or if the extent of caries is high [14]. Large restorations (49.4%) followed by crown build-up (31.5%) were the most common restorative options for which the participants of this study preferred using amalgam.
Esthetics (77.1%) followed by patients’ desire (58.6%) were reported as the most common reasons to restrict the use of amalgam by the participants of this study. Vidnes-Kopperud et al. [14] reported that the participants of their study preferred to use tooth-colored restorative materials in areas of the mouth that are visible. The authors also concluded that the participants considered esthetics as more important for females. Furthermore, Espelid et al. [13] reported that esthetics were of major concern for patients over longevity of the restorations irrespective of gender. About 27% of the participants of this study reported Mercury toxicity as a reason for restricting the use of amalgam. A survey conducted in Saudi Arabia in 1995 [16] reported that the majority of the dentists (85%) believed that amalgam is safe for patients but 88% indicated that it is hazardous to the dentists if not handled properly.
About 72% of the participants of this study disagreed on replacing good amalgam restorations with resin composite. On the other hand, the survey by Khairuldean and Sadig [16] reported that 63% of their respondents would explain their beliefs to the patients before removing amalgam, 21% would remove amalgam restoration upon patients’ request, 14% would not comply with the patients’ request whereas, 6% would encourage the patients to replace amalgam restoration with an alternative restorative material. A study comparing the mercury levels in general dentists with that in other health professionals using toenail clippings as a biomarker concluded that the number of dental amalgams was not related to the level of toenail mercury levels among dentists, dental specialists and patients. However, the toenail mercury levels of general dentists were found to be more than twice that of non-dental health professionals. The authors also suggested that the avoidance of amalgam cannot be justified by the presence of mercury released from dental amalgam [25].
Amalgam was reported as the most common restorative material of choice (80.1%) in case of changing an existing defective amalgam restoration by the participants of this study. This may be due to the benefits of amalgam perceived by dentists such as less risk of secondary caries compared to tooth colored alternatives [26] or due to operator skills or technique sensitivity involved in restoring with resin composites [5, 27].
The limitations of this study should be considered when interpreting the results. The sampling methodology and cross-sectional study design implemented in this study are major limitations. All dentists working in Riyadh may not be sufficiently represented while using a convenience sample. Although we intended to assess the attitudes of Saudi dentists and interns regarding the use of amalgam, inclusion of non-Saudi dentists would have made the study sample more representative of the dentist population working in Riyadh. A comparative assessment of all aspects of our results with that of similar previous studies [15, 16] was not always possible due to differences in questions and answer choices.